Method for manufacturing buried insulating layer type single crystal silicon carbide substrate

Abstract

Provided is a manufacturing method of a buried insulating layer type semiconductor silicon carbide substrate excellent in flatness of an interfaces in contact the insulating layer and a manufacturing device thereof. In the manufacturing device, an SOI substrate having a buried insulating layer positioned on a silicon substrate and a surface silicon layer formed on this buried insulating layer is placed in this film formation chamber. The manufacturing device includes: the film formation chamber in which the SOI substrate is placed; a gas supplying unit for supplying various types of gasses required for the manufacturing of a buried insulating layer type semiconductor silicon carbide substrate into the film formation chamber; an infrared ray irradiating unit for irradiating the surface silicon layer of the SOI substrate with infrared rays; and a control part for controlling the gas supplying unit and the infrared ray irradiating unit.

1. A method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate within a film formation chamber after placing, in this film formation chamber, an SOI substrate having a buried insulating layer positioned on a silicon substrate and a surface silicon layer formed on this buried insulating layer, wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized by comprising a first step of irradiating the surface silicon layer of the SOI substrate with infrared rays while supplying a mixed gas of hydrogen gas and hydrocarbon gas into the film formation chamber and, thereby, raising the temperature of the surface silicon layer to that required for metamorphosing the surface silicon layer into a single crystal silicon carbide thin film wherein this condition is maintained for a predetermined period of time so that the surface silicon layer is metamorphosed into a single crystal silicon carbide thin film. 
   
   
     2. The method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate according to  claim 1 , wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized by comprising: a second step of maintaining the same condition as of said first step for a predetermined period of time after said first step and, thereby, depositing a carbon thin film on said single crystal silicon carbide thin film; and a third step of replacing said mixed gas with an inert gas with oxygen gas mixed at a predetermined ratio and at the same time, achieving the temperature required for etching and removing said carbon thin film through the control of the irradiation of the infrared rays wherein this condition is maintained for a predetermined period of time so that the carbon thin film is etched and removed. 
   
   
     3. The method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate according to  claim 2 , wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized by comprising: a fourth step of replacing said inert gas with a pure inert gas with no oxygen gas mixed in after said third step and, after that, achieving the temperature required for making a new single crystal silicon carbide thin film to grow on said single crystal silicon carbide thin film through the control of the irradiation of the infrared rays while supplying a mixed gas of hydrogen gas and a silane based gas into the pure inert gas atmosphere wherein this condition is maintained for a predetermined period of time so that a new single crystal silicon carbide thin film is made to grow on the single crystal silicon carbide thin film. 
   
   
     4. The method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate according to  claim 3 , wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized in that said SOI substrate is a SIMOX substrate. 
   
   
     5. The method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate according to  claim 3 , wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized in that the film thickness of said surface silicon layer is 10 nm or less. 
   
   
     6. The method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate according to  claim 3 , wherein the method for manufacturing a buried insulating layer type semiconductor silicon carbide substrate is characterized in that the air pressure within the film formation chamber is set at atmospheric pressure.